Self-priming centrifugal pump



June 3, 1941.

H. E. LA BOUR SELF-PRIMING CENTRIFUGAL PUMP Filed May 26. 1938 6Sheets-Sheet 1 w w a 2+ w 4 4 f2 i 4 1% J W w m 3 n 3 s N 9/ V IL\\\June 3, 1941. H. E. LA BOUR 2,244,397

SELF-PRIMING CENTRIFUGAL PUMP Filed May 26, 1938 6 Sheets-Sheet 2 June3, 1941. H. E. LA BOUR SELF-PRIMING CENTRIFUGAL PUMP Filed May 26, 19386 Sheets-Sheet 4 June 1941- H. E. LA BbuR 2,244,397

SELF-PRIMING camauum. PUMP Filed May 26, 1938 6 Sheets-Sheei 5 June 3,1941. 5, LA ou 2,244,397

SELF-PRIMING CENTRIFUGAL PUMP Filed May 26, 1938 6 Sheets-Sheet 6Patented June 3, 1941 UNITED STATES PATENT OFFICE SELF-PRIMINGCENTRIFUGAL PUMP Harry E. La Bour, Elkhart, Ind. Application May 26,1938, Serial No. 210,131

(Cl. 103ll3) 20 Claims.

The present invention relates to self-priming centrifugal pumps. Whilethe specific embodiment herein shown is intended for general hydraulicservice rather than the more exacting chemical service, it is to beunderstood that the specific form herein shown and the service for whichit is intended are not limiting, but illustrative.

The pump herein disclosed embodies improvements which are capable ofbeing employed in various forms and for various uses. Also, the pumpherein disclosed contains two distinct im provements embodied in thesame structure. The first is that of a self-priming centrifugal pumpwhich may be used in either a horizontal or vertical position withoutchange of the operating parts which make it self-priming and, second,the concept of building a pump of such construction that the Wearingparts may be made of one metal, such as a durable, wear-resisting metalor alloy, whereas the main frame or body may be made of another metal oralloy, such as a light-weight metal to reduce the overall weight of theunit.

The pump herein illustrated and described embodies a number of desirableobjectives in pump construction, among others the following:

1. A self-priming pump which may be used in either the horizontal or thevertical position without alteration of the pump structure.

2. A pump having the suction and discharge connection and operatingparts so located that all the operating parts may be replaced withoutdisturbance of the pump shell on its mounting and without disconnectingeither the suction or the discharge.

3. A pump having a construction permitting interchangeable casings andimpellers to suit different head and capacity requirements and the like,thus lowering manufacturing costs.

4. A pump having all the working parts so reduced in size and isolatedfrom the large, expensive castings, that these working parts may bereplaced at a minimum cost.

5. A pump of simple design, permitting low cost and compact constructionreducing space requirements.

6. A pump wherein the parts subjected to severe wear may be made ofmaterials most resistant to wear, and yet keeping these parts reduced insize and weight so that they will not be excessively expensive. At thesame time, this pump permits the use of a light-weight material such asaluminum or aluminum alloys for the larger parts which would normallyhave the greatest effect on the Weight of the pump.

7. A pump which permits the use of the type .of casing employing theso-called trash type impeller, and a large open throat of the typedisclosed in my copending applications, Serial No. 118,032, of December29, 1936, and 175,187, of November 18, 1937.

8. A pump permitting the use of a multiple throat construction of thetype shown in Patent No. 2,110,883, of March 15, 1938.

9. A pump permitting the use of a mechanically sealed gland so arrangedthat it normally operates under suction only, thereby being protectedwhen the pump is operating with dirty or gritty liquid.

10. A pump and gland construction so arranged that the gland may beremoved or replaced from the front of the pump without disturbing anymore parts than would be necessary for the replacement of an impeller asreferred to in paragraph 2 above.

11. A pump consisting of a main body casting and an impeller housinginsertible into and removable from the main body and wherein only asingle gasket is required for these parts.

In attaining the above objectives a number of structural features ofnovelty are involved, among them being the following:

(a) Disposing the inlet trap upon the shaft side of the pump with theinlet opening uppermost in either position.

(b) Disposing the discharge trap or separator with its outlet on theshaft side of the pump so that the outlet is uppermost in eitherposition of the pump.

(0) Providing a check valve for the intake trap or intake of a pump ofthe class herein described operable in either the horizontal or verticalposition without change.

(d) Providing a complete hollow body with an opening adapted to receivethe active pump parts and to be closed by insertion of the pump partsinto the body.

(6) Providing a separate impeller casing or housing which is dividedinto two parts on the diameter of the impeller and mounting one part onone wall and the other part on another wall of the hollow pump body.

(1) Mounting one of the parts of the impclller casing or housing on orintegral with the closure platethat closes the external opening into thebody.

(9) Eliminating all gaskets except one, i. e., the

one that closes the outside opening.

like reference numerals designate like parts--- Figure 1 is a sectiontaken from the shaft side of the pump, that is, from the right of Figure2 on the line l--l of Figure 2;

Figure 2 is a transverse, generally vertical section taken on the line2-2 of Figure 1;

Figure 3 is a top plan view showing particularly the location of thecheck valve and the walls which separate the inlet from the discharge orseparator;

Figure 4 is a fragmentary cross-sectional view taken on the line 4-4,showing the position of the gravity operated check valve in the intakeconnection;

Figiu'e 5 is an elevational, partly sectional view similar to Figure l,and taken on the line 5-5 of Figure 6-, showing the same main frame witha different form oi impeller and impeller housing, to form amulti-throat self-priming D p;

Figure 6 is a vertical sectional view taken on the line 6-6 of Figure 5;

Figrue 7 is a section taken on the line 'l-1 of Figure 5;

Figure 8 is a side elevation, partly in section, taken on the line 8-8of Figure 9, showing a self-priming single throat pump usable in eitherhorizontal or vertical position;

Figure 9 is a rear elevational view of the same;

Figure 10 is a view like Figure 8, showing a single throat self-primingpump usable in either horizontal or vertical position without an intaketrap; and

Figure 11 is a similar view of a further modiflcation in which the inletis upon the shaft side of the pump casing.

The illustrations of Figures 8, 9, 10 and 11 are largely diagrammatic.

Now referring first to the form of pump shown in Figures 1 to 4,inclusive, it will be seen that the pump comprises, first, the mainhousing or frame unit H and second, the cover plate and impeller housingunit l2. A third main stationary part is the side plate and inlet memberl3. The chief moving parts comprise primarily the impeller l4, itsconnected shaft l5, and the riving shaft section I6. A packing glandunit, generally designated by the reference numeral ll, of themechanical seal type, seals the moving system to the stationary housingII, as will be described more in detail, hereinafter.

Referring first to the main frame and housing unit II, this unitcomprises substantially, and in a preferred form, a hollow unitarycasting of aluminum or aluminum alloy. Obviously, the material of whichthe unit H is made is optional within the invention, but by the use ofaluminum or aluminum alloys a large amount of weight is avoided, sincethis comprises the most expensive structural feature of the pump. Thismain unit is hollow and is formed with a generally semieylindricalbottom wall l8, vertically extending end walls l9 and 20 tangent to thecylindrical bottom wall I8, and a substantially flat top wall 2| which,preferably, is approximately at right angles to the walls l9 and 20. Aflat front wall 22 which, in the position shown in Figures 1 and 2, issubstantially vertical, has a large circular opening 23 disposedsubstantially concentric with the axis of the impeller l4 and its shaftiii. A substantially parallel back wall 24 has a central hub or boss 25for receiving the packing gland unit N. This hub or boss 25 is likewisesubstantially concentric with the axis of the impeller and its shaft. Anintermediate wall 26 extends down from the top wall 2| and is joined toa curved cylindrical bottom wall 21 to define an intake passagewaygenerally designated as 28. The lateral flanks or sides of this inletpassageway 28 are defined by vertical Walls 29 and 30 (see Figure 1) andthe intake passageway 28 then extends substantially horizontally, in theposition shown in Figures 1 and 2, to a flanged inlet opening 32.

In the horizontal portion of the inlet passageway and trap 28 there isdisposed a valve port 34 having a valve seat disposed obliquely withrespect to both a vertical line and a horizontal line. This valve seat35 is shown in dotted lines in Figure 4. It is adapted to be closed by agravity operated flap valve 36 having a suitable facing 31 and beinghinged upon a pin 38 the axis of which also is oblique to a horizontalplane when the pump is in either a vertical or a horizontal position.The pin 38, in the present case, is mounted in a pair of lugs 39 carriedby the cover plate 45. This cover plate 40 is held over the flangedopening in domed wall 42 as by means of a hooked clamping bar 43 and acentral set screw 44. Obviously, instead of a fixed pin hinge, aflexible or fabric hinge of known construction might be employed, andalso it is to be observed that instead of a flap valve a gravityoperated ball valve might be employed, it being understood that in thatcase the ball would fall by gravity to the seat of the valve port,whether the pump be in vertical or in horizontal position.

The space within the main casing unit not employed by the intake trapand passageway 28 and lying outside of the pump impeller casing, forms aseparating space or chamber 45. This separator forms a trap when thepump is in either a horizontal or vertical position, by virtue of theplacement of the discharge or outlet opening 46 at the top of theseparator chamber 45 when the pump is in the horizontal position asshown in Figures 1 and 2, or in the vertical position, that is, when theshaft I6 is disposed in a vertical position. The discharge outlet 46 hasa surrounding coupling flange 41 and this opening 46 leads to the insideof the separator 45 through a lateral passageway 48 which, in effect,forms a dome into which the air tends to gravitate when the pump is ineither a horizontal or vertical position.

It will now be observed that the inlet opening 32 and the discharge oroutlet opening 46 are disposed substantially in line and at the upperinner corner of the main frame unit, so that whether the pump be in thehorizontal position shown in Figures 1 and 2 or in the vertical position(not shown), the inlet and outlet openings 32 and 46, respectively, areso disposed that they tend to trap liquid in the intake and in theseparator chamber, whereby a charge of priming liquid is provided.

The intermediate wall 26 and the semi-cylindrical wall 21, with the sidewalls 29 and 30, merge into a short tubular neck having a large circularopening surrounded by the clamping flange 49. This opening isintermediate in size between the relatively large opening 23 which isclosed by the cover plate and the relatively small opening for the shaftin the opposite wall. This clamping flange has a planar surface againstwhich is clamped the corresponding planar surface of the inlet sideplate member 13. The said side plate member 18 has a radial shoulder atii to pilot the side plate member 133 accurately in the opening in theflange 49. The member l3 has a flared conical wall 52 with a centralopening 53 through which the shaft of the impeller member 14 extends andwhich also forms communication between the inside of the impeller casingand the intake trap 28.

In the form shown, the main frame or housing casting H is made ofaluminum or aluminum alloy which is relatively soft, hence, to bolt tothe relatively thin walls it is preferable not to cut threads in themain casing or body portion. In clamping the side plate l3 upon theflange 49 the studs 54 are set or threaded into the wall 52 of the sideplate member l3, which is of a wear-resisting material and hence harderand stronger than the metal of the flange 49. Similarly, in bolting theunit [2 over the opening 23,

the bolts 55 are inserted from the inside through openings formed in thewall 22, these bolts having knurled or fluted portions such as 56 tokeep them from turning when the clamping nuts 51 are drawn tight.Similarly, the bolts 58 employed for clamping the main body portion tothe mounting plate or member 59 secure the clamping of these parts inthe aforesaid manner.

The adapter plate 59 may be varied with the mounting of the pump, but inthe form shown in Figure 2 it couples the flanged bell housing 80 of aninternal combustion engine to the main frame ll of the pump.

The cover and impeller casing unit 12 consists of a circular disc-likemember having a flange piloted into the opening 23 and clamped under thebolts 55 to the front wall 22, a suitable gasket 8| being interposed tomake a tight joint. This unit 12 has cast integral therewith theperipheral impeller housing portion 62. This impeller housing 62comprises the operating features of a pump casing in combination withthe side plate 13. That is to say, there is a circular opening in theimpeller housing portion of the unit l2 which fits fairly closely theperiphery of the inlet side plate member 13. The joint at 63 is intendedto be a fairly close fit. Packing might be employed at this point but itis not-l particularly necessary, since the volute channel G4 defined bythe periphery of the impeller casing is always under pressure when thepump is in operation, and leakage out into the separator does noparticular harm. The joint is located at the tips of the impellerblades, where substantially maximum pressure prevails at all times thatthe impeller has sufficient liquid to operate upon.

Obviously, the impeller housing, as such, might be split on the leftside of the volute wall as viewed in Figure 2, instead of on the rightside. That is to say, the volute and side plate member 13 might beintegral instead of having the volute 62 and the side plate member 65integral. There are several advantages in the construction shown; first,that it is easier to get at the imill peller and the fastening means,such as the bolts 54, when the volute housing 62 is made integral withthe cover plate member l2, and, second, the weight and the forces ofpumping are better supported on the large circle of bolts 55 than on thesmaller circle of bolts 54.

The volute portion 62 of the housing comprises the cut-off portion 66(see Figure 1), which has a machined surface just clearing the tips ofthe impeller blades 61, 61 of the impeller 14. The volute also comprisesa spout portion 68 with the outlet opening 69 and lateral inlet openings'18, 18 through which openings 18, 10 priming water may return into theperiphery of the impeller to be mixed up with air in the impeller casingduring priming and ejected out of the spout 69. It is to be observedthat the inlet trap and separator are so related to the pumping casingand impeller that re-entry of priming water will occur during thepriming operation but will be prevented from re-entry during liquidpumping.

The method of operation of the pump shown in Figures 1 to 4 is broadlythat of my basic Patent No. 1,578,236, of March 23, 1926, andspecifically that of the pump disclosed in my copending application,Serial No. 175,187, above referred to.

The impeller M as shown herein is fastened as a unitary member upon theend of the shaft section 15. The shaft section I5 is bored out toprovide a cylindrical socket 12 to receive the reduced portion 13 of theshaft section 16 in telescopic relation, these parts being keyedtogether as indicated by the key at 14. The shaft section I5 iscounterbored to provide a shoulder 15, resting against the shoulder 16of the shaft section 16. At the outer end of the shaft section 16 amounting plate or spider TI is likewise counterbored to provide ashoulder 78 cooperating with a shoulder '19 on the shaft section I6. Thehub of the member 71 has an annular wear shoulder 80 which may be facedwith a metal highly resistant to wear, and the shaft section l5similarly has a wear shoulder 82, likewise faced with a material highlyresistant to wear, for engagement with the stationary rings 83 and 84 ofthe packing gland. These rings 83 and 84 are connected to rubberdiaphragm members 85 and 88, respectively, having radial flanges clampedto a central block 81 by means of aligned cylindrical cheek pieces 88and 89 which are held to gether by longitudinally extending bolts 98,whereby the packing gland member is a unitary, axially expansible devicemounted upon the impeller shaft but releasable by separating thesections I5 and IS. A guiding sleeve 92 which preferably but notnecessarily is a unitary cylinder is keyed or pinned to the end rings 83and 84 and to the central block 81 to prevent turning of the rings 83,84 and to hold the rings 83, 84 and the diaphragms 85, 86 in alinement.The external cylindrical surface of the gland unit is fitted fairlyclosely in the bore of the hub member 25, in which it is axiallyadjustable to the desired position. Upon being adjusted to the desiredposition it may be fixed and sealed in place by means of the studs 93and clamp ring 94 which compress a packing 95 upon the cylindricalsurface of the cheek piece 88.

While I have herein shown and above described one form of a packingunit, I prefer to employ the particular form of packing unit shown in mycopending application, Serial No. 206,425 filed May 6, 1938.

While in the specific form of packing unit herein shown, an adequateseal is produced if the shaft section I6 runs fairly true, the packingunit shown in my copending application above referred to, permits notonly of axial play but of lateral or, in fact, universal movement, eventhough the shaft l6 be subject to appreciable eccentricity or wobble.

The two shaft sections are held together by a screw bolt 96 which seatsin a bore in the outer end of the shaft section ['5, this bore beinclosed by a pipe plug 91.

In casting the impeller upon the end of the shaft section l5, the shaftsection is first threaded, as indicated at 98, and provided with atransverse pin or key 99. Then the shaft is put in the mold and. the hubof the impeller cast around the same with the blades integral.Thereafter, the shaft section l5 and the impeller are suitably finished,as by grinding and machining.

The mounting plate or spider H is clamped, as by bolting, upon asuitable seat on the engine flywheel Hill which, in turn, is carriedupon the flange I02 of the engine crank shaft I03, which crank shaft issupported in suitable bearings I04 rigid with the bell housing 60, sothat the stationary parts and the movable parts are all held accuratelyin alignment.

When it is desired to remove the impeller the cover plate and housingunit I2 is released by releasing the bolts 55 so that the unit may bepulled off of the housing unit H, revealing the impeller I4. Thereuponthe pipe plug 91 is unscrewed, the screw 96 is released, and the shaftsection I5, with the impeller I4 thereupon, may be pulled off of thestud or reduced shaft portion 13. The impeller may then be replaced, ifdesired, or, if desired, the packing gland unit l1 may be released andwithdrawn, leaving the shaft section l6 in place. Also, at this time,the side plate member l3 may be replaced or interchanged, if desired.All of these operations may be performed without disturbing the pipeconnections, the mounting of the pump, or any other fixed part.

Only one gasket is required and that is the gasket 6|, which is externaland easily accessible. Variations in the thickness of the gasket or thedegree to which it is tightened have no adverse effects, within limits,upon the fit of the impeller casing nor upon the tightness of the innerjoints.

The check valve is likewise accessible for inspection, renewal, cleaningand the like, without disturbing any of the pipe connections or any ofthe other fastenings.

It is to be understood that instead of the particular form of glandabove disclosed, any other form of gland having a flange taking theplace of the ring 94 and being capable of being clamped in place mightbe employed, such packing gland requiring no specific axial location onthe shaft sections [5 and I6, which need to provide only a cylindricalsurface.

While I have not shown the lubrication circulation feature disclosed inmy copending application above referred to, it is to be understood thatwhere the same is employed the reservoir will extend upward and to theright as indicated in Figure 2, so that the reservoir will be uppermostwhether the pump is in the horizontal or in the vertical position.

In operation, the pump is mounted as, for example, by means of the bellhousing 60 or any other suitable mounting, and it is to be understoodthat the mounting may be widely varied. For example, the independentbracket or bearing construction shown in my prior Patent No. 1,993,999,of March 12, 1935, is intended as one method of mounting the pump in ahorizontal position.

If the pump is to be mounted in a vertical position the shaft l5, l6extends vertically upward and the pump may be mounted, for example, bylegs integral with the cover and housing unit l2, or the pump may besuspended from a sup-port such as a bell housing 60 connected to a motoreither of the electric or internal combustion type, the various methodsof supporting the same being, I believe, within the skill of the art.

The suction and discharge pipes or hoses may be connected to the flanges33 and 41 as by mating flanges and, assuming the pump to be in thehorizontal position as shown in Figures 1 to 4, inclusive, the pump maybe filled with liquid by releasing the cover plate 40 and the checkvalve 36 and introducing water into the inlet trap 28. The valve andcover plate being replaced, the impeller is then rotated in a clockwisedirection as viewed in Figure 1. The impeller l4 herein shown is simplyone form of impeller which may be employed, it being understood that anysuitable impeller desired for the particular operation for which thepump is adapted may be employed. Upon rotation of the impeller, liquidis driven out of the impeller housing, out of the spout 68, and into theseparator space 45. As soon as this is accomplished, air enters theimpeller and the resultant pressure developed by the impeller on airbeing insufficient to overcome any appreciable back pressure of thehydrostatic head of the liquid, liquid flows back into the impeller assoon as the drop in pressure permits, and liquid and air are churned upor mixed in the impeller housing and driven out of the spout 69. Themixture tends to follow the inner peripheral wall of the volute 62 and,following this wall, is lifted away from the impeller so that theimpeller has a region of low pressure at about the openings '10, andliquid freed of air returns through these openings into the impeller,continuing this recirculation and evacuation of air until the desireddegree of vacuum in the suction passageways pulls liquid over, and thenpumping proceeds with the discharge of liquid out of the spout 69 andsome of it out through the openings 10. The flow reversing at theopenings 19 provides additional outlets and tends to prevent anyclogging of the said openings.

While I have shown the spout 68 as directed upwardly, in the lower lefthand quarter of Figure 1, it is to be understood that since the mountingof this housing unit is on the cover plate member l2, any desiredposition of the spout 68 about the axis of the shaft may be secured ifdesired. I prefer the disposition of the spout 68 within the lower halfof the casing in order to insure adequate travel of the mixture to thesurface of the liquid in the separator and adequate sealing of thereturn opening 10 during the priming operation.

When the pump is in the position shown in Figures 1 to 4, that is, withthe shaft horizontal, the level of water in the separator will be in ahorizontal plane parallel to the shaft, but if the pump is placed in avertical position the level of the water will be at right angles to theaxis of the shaft, but no substantial difference in mode of operationresults, since the level of liquid in the separator will be maintainedhigh enough, because of the location of the outlet 46, to sealadequately the openings 16 and also to provide a free surface for theseparation of the air from liquid.

Obviously, the right hand opening I shown in Figure 2 might be closed oromitted if the pump were to be used only in vertical position. In thatcase a larger opening in the bottom side of the volute, corresponding incapacity to the two passageways III-I0 might be provided.

Upon the cessation of pumping, liquid tends to run back through the pumpand down the suction pipe to the source. The check valve 36 is intendedto stop this, chiefly for the purpose of saving the escape oi too muchliquid from the inlet pipe or trap 28. Without some means of retardingthe back flow, there might be times when the backward rush of liquidthrough the pump down to the source would carry too much of the liquidout of the pump unit for satisfactory priming on the next operation.Hence, the check valve 36, even if it should leak, will prevent suchback rush of water and will thereby insure the trapping of an adequateamount of priming liquid in the pump.

While the outlet and inlet openings are shown axially in line, it is tobe understood that this is optional, the desirable feature being thatthey be at approximately the same level for the trapping of liquid, fortrapping is the most reliable method of retaining the charge of primingliquid. For general operation this is the preferred manner, but it willbe obvious that within my invention, reliance may be put upon a checkvalve, operating in either the horizontal or the vertical position ofthe pump, for retaining an adequate charge of priming liquid in theseparator and pump casing.

In Figures 5, 6 and 7 I have shown the main frame or shell II asprovided with a cover and impeller housing unit I2 having multipleoutlets and embodying the structure and mode of operation disclosed andclaimed in my prior Patent No. 2,110,883. The impeller unit I4 is of atype which substantially sweeps the periphery of the casing betweenmultiple outlets and is of any preferred type, such, for example, asthat shown in the aforesaid Patent No. 2,110,883. The tips of theimpeller blades 67', 61, describe the circle I61 and with little morethan mechanical clearance they sweep the inner cylindrical portions ofthe periphery of the impeller housing 62. In the embodiment shown inFigures 5, 6 and 7 there are two sets of discharge throats or outletsfrom the impellerhousing 62', namely, the main throats I08, I09 whichterminate in divergent passageways H6 and H2, respectively, and theauxiliary throats H3 and III which likewise diverge into passages H andH6 (see Figure 5). The casing 62' is substantially concentric from thepoint III to substantially the point H8 in advance of the throats I98and H3 and likewise, on the other side, the casing is concentric fromthe point H9 to substantially the point I20 in advance of the throatsI69 and H4. These throats and their passageways are substantiallytangential, outwardly flaring passageways for reducing the velocity offlow of the liquid discharged by them respectively during liquidpumping.

It will be observed that the throat H4, instead of discharging in theplane of the impeller, opens out sidewise as indicated at on each sideof the casing 62', there being a wedge-shaped prow or wall I22 fordividing the ture from one of the main throats from reaching too quicklythe auxiliary or priming throat during the priming operation, I haveprovided a baiile arrangement comprising the arcuate baffle I23 whichextends from the point I24 above the outlet III) of the main throat I68on the right hand side of Figure 5 to a point I25 substantially beyondthe outlet 2 of the main throat I09. An integral web I26 lies upon theopposite side of the impeller housing 62 and is formed preferablyintegral with the cover plate and housing unit I2, as may be seen fromFigures 6 and 7. The baIlle arrangement operates during priming asfollows. Assume that the pump casing has been charged with a primingcharge of water and the suction hose lowered into a source of water, thepump is started into rotation in a clockwise direction as viewed inFigure 5. The impeller promptly discharges the water from the impellercasing and empties the intake passageway 28, drawing air into theimpeller and impeller casing. Liquid then tends to return through theauxiliary passageways H5 and H6 through the throats H3 and H4 intocontact with the tips of the impeller blades. This priming liquid ismixed with air and carried by the impeller blades to the respective maindischarge throats I68 and I09, where the mixture is dischargedcontinuously so long as priming proceeds. It will now be observed thatthe mixture discharged from the main outlet III] is directed inside themain separator chamber below the arcuate bailies I23 and I26 and isdriven around in a clockwise direction to the left to where it is joinedwith the discharge from the other main outlet II2. Thereupon the mixtureof air and liquid, some of which has tended to separate by gravity inthe meanwhile, is "driven upwardly, at the left of Figure 5, towards thesurface of liquid in the separator with the result that air escapes atthe said free surface of the liquid, and liquid from which air has beenseparated flows over towards the left in a generally clockwise directionand then drops down on the upper side of the baiiie I23 and I26, some ofthe liquid flowing into the auxiliary passageway II5 as indicated by thearrow I28 on Figure 5. Other parts of the liquid not flowing into thepriming throat II5 continues as indicatcd by the arrow I29 (Fig. 5) andflows upwardly to the auxiliary throat H6 and enters as indicated by thearrow I33 on Figure 5.

A like flow occurs on the opposite side of the impeller casing 62',where the side plate of the unit I2 and the arcuate ballle I26 forms apassageway IE'I communicating, on the left-hand side, as viewed inFigure 6, with both of the auxiliary passageways H5 and H6. In thismanner, priming proceeds in an orderly fashion without danger ofshort-circuiting mixture from a main discharge throat immediately to oneor both of the auxiliary throats. Thereby the mixture discharged isgiven ample time to produce separation of the gas from the liquid.

The normal level of liquid in the separator will be at, or sligh lybelow the bottom of the discharge opening 46, as viewed in Figure 5 andin Figure 1.

The structure of the packing gland and the general method ofconstructing the impeller and the driving shaft thereof for the pumpshown in Figures 5, 6 and 7 may be the same as that described inconnection with Figures 1 to 4, inclusive, or any other preferred formof construction for these parts may be utilized.

Thus it will be apparent that within the aforesaid teaching in regard tothe renewable or interchangeable impeller and easing, I have shown inFigure 1 a volute type of casing and trash type of impeller, while inFigures 5 and 6 I have shown the concentric type of impeller casing anda substantially straight bladed type of impeller.

The pump casing 62' may be of the volute type with a volute andcorresponding outlet for each half or third of the circumference of theimpeller. That is to say, each outlet becomes during priming a means fordischarging mixture and for the reentry of liquid to be mixed with gas'and ejected at the next succeeding outlet.

Within the teaching of my invention the construction of a pump for usein either horizontal or vertical position may be accomplished withoutthe removable or interchangeable impeller housing, as illustrateddiagrammatically, for example, in Figures 8 and 9.

As shown in Figures 8 and 9, an impeller casing I40 containing animpeller MI is provided with a separator I42 having the lateralextension I43 at the upper shaft side. so that the outlet I44 will beuppermost whether the pump be in the horizontal or in the verticalposition. Likewise, the impeller housing I40 has the intake trap I45located on the shaft side, and it terminates in an outlet I46 which issubstantially in line with and at the same level as the discharge outletI44.

The shaft I41 for the impeller I4I extends through a stuffing box of anydesired type I48, in a wall of the intake trap I45. The impeller casingI40 may be of the volute type, having a cut-off at I49, shown in dottedlines in Figure 9, a discharge spout I50, as shown in dotted lines inFigure 9, and the lateral inlets I52, I52 in accordance with theteachings of my copending application Serial No. 175,187 above referredto.

The operation of the pump shown in Figures 8 and 9 will be apparent fromthe above description, namely, that it will operate as a selfprimingpump in either the horizontal or in the vertical position of the shaftI41. If desired, a suitable check valve such as the double positioncheck valve 36 shown in Figure 1 may be employed in the intake trap I45or in the passageway leading thereto, but it will be understood thatthis is optional.

Also within my invention, the intake trap as a means for retaining acharge of liquid may be dispensed with and reliance placed upon atwo-positional check valve I53, as shown in Figures and 11. In that casethe intake passageway may be placed opposite the shaft side, as at I54in Figure 10, or it may be placed on the shaft side, as at I55 in Figure11 of the impeller casing. The impeller casing may be of the volute typeabove referred to in connection with Figures 8 and 9, having a spout I50disposed above the bottom of the separator I42, with side inletpassageways such as I52 serving as auxiliary inlets and dischargepassageways during priming and liquid pumping, respectively.

Where the pump is to be made up for vertical use only, the type of glandshown in my copending application, Serial No. 206,424, filed May 6,1938, may be employed.

It will be apparent to those skilled in the art that numerousmodifications in detail may be made without departing from the spirit ofmy invention. I do not intend, therefore, to be limited to the detailsshown and described, except as they are significantly recited in thefollowing claims.

I claim:

1. A self-priming centrifugal pump capable of operating in either avertical or a horizontal position, comprising an impeller casing havinga centrally disposed inlet opening and a peripheral discharge, animpeller in the casing having a driving shaft extending from one side ofthe casing, a separator chamber communicating with the discharge of theimpeller casing and having a discharge outlet disposed at a sufficientradial distance from the axis of the shaft to provide a trap for acharge of priming liquid when the shaft is horizontal and at asufficient axial distance from the plane of the impeller and on theshaft side of said impeller casing to provide a trap for a charge ofpriming liquid when the shaft is vertical, means submerged in thetrapped liquid in either horizontal or vertical position of the trap'for returning priming liquid into the impeller casing during primingand an intake connection having means for preventing the escape of apriming charge of liquid when the pump is disposed in either horizontalor vertical position.

2. The pump of claim 1 having an intake trap in the intake connection,said trap having an inlet opening lying at approximately the same radialdistance from the axis of the shaft and at approximately the same axialdistance from the plane of the impeller, respectively, as said dischargeoutlet.

3. The pump of claim 1 wherein the means in the intake connectioncomprises a swinging flap valve the axis of which is diagonal to theplane of the horizon and the valve tends to close by gravity when thepump is in either the horizontal or the vertical position.

4. A self-priming centrifugal pump operable in either vertical or inhorizontal position, comprising an impeller casing having a centralinlet and a discharge outlet, an impeller having a driving shaftextending out of said inlet, a separator communicating with thedischarge outlet and having means for retaining a charge of primingwater during priming when the pump is in either position, said meanscomprising an outlet opening disposed at substantially the junction ofthe top and side walls of the separator whereby said opening isuppermost in either position of the pump and an intake trapcommunicating with the inlet of the casing and having means to preventthe escape of priming water during the time the pump is not operatingand when the pump is in either position.

5. The pump of claim 4 wherein the intake trap has an intake openingwhich lies above the inlet opening of the impeller casing in either ofsaid positions of the pump.

6. In a pump, a combined integral impeller housing and cover plate unitcomprising a circular imperforate disc-like member having sealing andpiloting surfaces at its margin for mounting the unit in a circularopening, the impeller housing comprising a peripheral pumping channelwith an integral side plate, said housing having a discharge throatleading from the inside of the channel to the outside thereof, saidhousing having a circular opening in the side thereof opposite saidintegral side plate large enough for the introduction of an impellerinto the housing.

7. The unit of claim 6 wherein the impeller housing comprises anintegral volute having a cutoff and a discharge spout, said dischargespout constituting during priming as means for conducting a discharge ofgas and liquid from the impeller housing and an inlet of liquid backinto the impeller housing.

8. In a pump of the class described, a main hollow body casting havinginlet and discharge chambers and a dividing wall between them, animpeller, a two part impeller housing for the impeller comprising firsta side plate carried by the dividing wall and being apertured for entryof fluid from the inlet chamber and second a main impeller housing partopen at one side to pass over the impeller and telescopically embracethe side plate, said second part comprising a closed side plate and amounting flange, means for attaching the mounting flange to the wall ofthe discharge chamber, and an impeller shaft extending through anopening in the wall of the inlet chamber.

9. In a self-priming centrifugal pump, a main hollow body casting havinginlet and discharge chambers, comprising respectively an inlet trap trapand a separator, and a dividing wall bea tween them, an impeller, a twopart impeller housing for the impeller comprising first a side platecarried by the dividing wall and being apertured for entry of fluid fromthe inlet chamber, and second a main impeller housing part open at oneside to pass over the impeller and telescopically embrace the sideplate, said second part comprising a closed side plate and a mountingflange, and a channel portion, said channel portion having peripheralthroating leading to the discharge chamber inside the hollow body, saidthroating comprising means for returning priming liquid from theseparator into the impeller during priming, means for attaching themounting flange to the wall of the discharge chamber, and an impellershaft extending through an opening in the wall of the inlet chamber.

10. A self-priming centrifugal pump adapted to operate in eitherhorizontal or vertical position comprising an impeller chamber providedwith an impeller and having an outlet, an inlet passageway leading intothe central part of the impeller chamber, a gas and liquid separatorcommunicating with the outlet of the impeller chamber and having adischarge outlet said outlet communicating with the inside of theseparator at the junction of the two walls which are top and side wallswhen the pump is horizontal and side and top walls when the pump isvertical, whereby a charge of priming liquid is retained in theseparator in either position, and means in the inlet passageway operablein either position of the pump to prevent the escape of said charge ofpriming liquid.

11. A pump of the class described comprising in combination a hollowintegral main body casting with internal walls dividing the space intotwo chambers constituting a separator and an inlet trap respectively,there being an insert opening in a wall of the separator, and a shaftopening in a wall of the trap in alignment with the imert opening. saidinternal walls comprising an annular rim defining an opening alignedwith said openings, an apertured inlet side plate detacha-bly secured tosaid rim, an integral imperiorate cover and impeller casing memberremovably attached to said main body portion with the impeller casingdisposed inside the separator with separating space surrounding theperiphery of the impeller casing, one side of the impeller casing havingan opening which permits insertion of the impeller, said last namedopening being closed by a sliding fit with the periphery of the sideplate, an impeller in said casing, and an impeller shaft extendingthrough the shaft opening.

12. An integral cast hollow pump body for a self-priming centrifugalpump comprising a housing which has walls defining a separator chamberand an inlet trap, said body having integral tubular discharge andintake connections communicating with said separator and traprespectively, the walls of the separator having a relative largeopening, the walls of the inlet trap having a relatively small openingfor an impeller shaft, said walls comprising an intermediate wallbetween the separator chamber and the trap with an opening ofintermediate size, said first and last named openings being eachsurrounded by an annular rim having an annular clamping face for theattachment thereto of impeller housing parts and said opening beingsubstantially coaxial.

13. In a centrifugal self-priming pump, the combination of an integralcast hollow pump body comprising a housing which has walls defining aseparator chamber and an inlet trap, said body having integral tubulardischarge and intake connections communicating with said separator andtrap respectively, the walls of the separator having a relatively largeopening, the walls of the inlet trap having a relatively small openingfor an impe ler shaft. said walls comprising an intermediate wallbetween the separator chamber and the trap with an opening ofintermediate size surrounded by an annular rim having an annularclamping face, an impeller housing side plate having a central opening,said side plate being clamped to said annular clamping face, animperforate cover plate clamped to the main body over said first namedopening, said cover plate forming an imperforate impeller housing sideplate, said cover plate having an integral impeller housing channelportion with an opening embracing the first named side plate, saidhousin'g channel portion bearing an integral hollow projection defininga discharge passageway which opens into the separator and beinginsertible and removable through said first named opening when the coverplate is applied and removed, an impeller in said housing, and a shafttherefor extending out through said shaft opening.

14. A self-primlng centrifugal pump adapted for operation with the shaftvertical, comprising a main hollow body casting having walls defining aseparator and an inlet trap, discharge and inlet connections from thetop of the separator and the trap, respectively, there being an openingin the bottom of the separator, an imperforate cover plate for closingsaid opening, the bottom of the inlet being defined by a tubular wall,an impeller housing side plate with a central inlet opening clamped tothe tubular wall, the cover plate having a part forming a cooperatingimpeller housing side plate, there being a peripheral housing portionintegral with one of said side plates and having a sliding joint withthe other of said side plates to define an impeller housing, saidperipheral housing portion defining an internal channel and having adischarge port and a reentry port opening into said separator, theseparator providing free space around the periphery of the housingportion, and an impeller in said impeller housing cooperating with saidchannel.

' 15. In apump of the class described, a hollow main body havingchambers constituting a trap and a separator, said body having aninternal wall between said trap and separator having a circular opening,an external wall for the separator having a circular opening inalignment with the IllSt opening, an impeller housing disposed in andsurrounded by the separator, an impeller in the housing, said housingbeing divided by a cylindrical telescopic joint of a diameter largeenough to clear the periphery of the impeller into two parts comprising,first, an integral side plate and channel member, the channel membercarrying one or more discharge spouts, and the side of the channelmember having a circular bore forming the external part of saidtelescopic joint and, second, a side plate member having a circularperiphery adapted to fit said bore and forming the internal part of saidtelescopic joint, one of said members having formed integral therewithan imperforate closure disc adapted to be clamped to the margins of theopening in the external wall and sealed by a compressible gasket, theother of said members being clamped over the opening in the internalwall and having a central inlet opening, and a shaft for the impellerextending through said latter opening and through the wall of the trap.

16. In a pump, a combined integral impeller housing and cover plate unitcomprising a circular disc-like member having sealing and pilotingsurfaces at its margin for mounting the unit in a circular opening, theimpeller housing comprising a peripheral pumping channel with anintegral side plate, said housing having a circular opening in the sidethereof opposite said integral side plate large enough for theintroduction of an impeller into the housing, said housing having aperipheral main discharge opening and a pcripheral auxiliary dischargeopening which latter opening is adapted to serve as a priming liquidinlet during the operation of self-priming, and a wall for shielding theauxiliary inlet from undue interference by the main discharge openingwhen the pump is priming.

17. For use in a self-priming centrifugal pump, a combined integralimpeller housing and cover unit comprising an imperforate closure memberhaving circular sealing and piloting surfaces at its margin for mountingthe unit upon a circular sealing seat, the impeller housing comprisingan integral impeller channel member and side plates, said channel memberhaving walls defining a pair of adjacent discharge passageways openingsubstantially tangentially out of the channel, said passagewaysconstituting a main discharge passageway and an auxiliary or primingpassageway, liquid directing means for directing the discharge of themain discharge passageway away from the auxiliary or priming passagewayto prevent interference during priming, said impeller housing having acircular opening in the side thereof opposite said integral side platelarge enough for the introduction of an impeller into the housing.

18. In a vertical centrifugal self-priming pump a pump body comprising asubstantially circular impeller housing disposed in a substantiallyhorizontal plane, said body comprising a casing defining a separatorchamber surrounding the impeller housing and extending above and belowthe plane of the impeller housing and adapted to provide an annular freesurface of priming liqu d during priming, a discharge outletcommunicating with the space above said free surface, said housinghaving walls defining a pair of adjacent substantially tangentialdischarge passageways opening at their inner ends into the inside of thehousing on substantially the same horizontal plane and communicating attheir outer ends with the separator chamber at different levels to avoidinterference during priming of a mixture discharged into the separatorby the one passageway with the return of liquid through the otherpassageway, and an impeller mounted for rotation on a vertical axisdisposed in said housing, and means to trap a charge of primin'g liquidin said pump body.

19. A centrifugal self-priming pump comprising a stationary part and arotary part, the rotary part comprising an impeller and a shafttherefor, the stationary part having three functional chambers, namelyan inlet chamber, an impeller chamber communicating centrally with theinlet chamber and peripherally with the discharge chamber, and adischarge chamber surrounding at least a part of the inlet chamber and apart of the impeller chamber, said stationary part comprising threeseparate members, namely a main frame member provided with fixed inletand discharge connections and comprising a part of the walls of theinlet and discharge chambers and having an opening for the impellershaft, an imperforate closure member provided with fastening means forsecuring it to the main frame member, said closure member forming a partof the walls of the discharge chamber and of the impeller chamber, anda. third member having a telescopic joint with the said closure member,said joint being substantially at the periphery of the impeller andlying within the discharge chamber, said third member having means forsecuring it to the main frame member and forming a part of the walls ofthe impeller chamber and of the inlet chamber and having an inletopening between the impeller chamber and. the inlet chamber throughwhich the impeller shaft extends out of the impeller chamber.

20. The combination of a pump body comprising ahollow casting having aclosed top wall with a central opening for a shaft in said top wall,said casting comprising outer and inner walls concentric with thecentral opening, the inner wall terminating in an annular rim, the outerwall terminating in an annular gasket surface lying below the said rim,said inner wall defining interiorly thereof a trap and the space betweenthe inner and outer walls defining a separator, tubular inlet anddischarge connections providing external communication with the upperend of the trap and separator, respectively, an annular top impellerhousing plate secured against the annular rim, said plate having acentral opening forming an impeller housing eye, and a closure platehaving a gasket surface cooperating with said firstnamed gasket surfaceand forming a closure for the lower end of the outer wall, said closureplate forming also a bottom impeller housing plate and having an annularwall cooperating with the top plate for closing the pcriphery of theimpeller housing, said annular wall having throating communicating withthe separator, and an impeller in the impeller housing, said throatingcomprising a pair of throats, and a directing fiange separating thethreats from each other.

HARRY E. LA BOUR.

